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<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
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<body>
  <script>
    /*
    // 声明一个年龄的变量
    let age;
    // 赋值
    age = 18;*/
    let age = 18;
    let name = 'caiwan';
    alert(age);
    console.log(age);
    console.log(name);

    // test
    let num = 20;
    let uname = '张三';
    console.log(num);
    console.log(uname);
  </script>
</body>

</html>